path: root/libavformat/rtpdec_svq3.c (plain)
blob: 18d79d2e22dad859a0240c8c3709d2901c7da629

1	/*
2	* Sorenson-3 (SVQ3/SV3V) payload for RTP
3	* Copyright (c) 2010 Ronald S. Bultje
4	*
5	* This file is part of FFmpeg.
6	*
7	* FFmpeg is free software; you can redistribute it and/or
8	* modify it under the terms of the GNU Lesser General Public
9	* License as published by the Free Software Foundation; either
10	* version 2.1 of the License, or (at your option) any later version.
11	*
12	* FFmpeg is distributed in the hope that it will be useful,
13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15	* Lesser General Public License for more details.
16	*
17	* You should have received a copy of the GNU Lesser General Public
18	* License along with FFmpeg; if not, write to the Free Software
19	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20	*/
21
22	/**
23	* @file
24	* @brief RTP support for the SV3V (SVQ3) payload
25	* @author Ronald S. Bultje <rbultje@ronald.bitfreak.net>
26	* @see http://wiki.multimedia.cx/index.php?title=Sorenson_Video_3#Packetization
27	*/
28
29	#include <string.h>
30	#include "libavutil/intreadwrite.h"
31	#include "avio_internal.h"
32	#include "internal.h"
33	#include "rtp.h"
34	#include "rtpdec.h"
35	#include "rtpdec_formats.h"
36
37	struct PayloadContext {
38	AVIOContext *pktbuf;
39	int64_t timestamp;
40	};
41
42	/** return 0 on packet, <0 on partial packet or error... */
43	static int svq3_parse_packet (AVFormatContext *s, PayloadContext *sv,
44	AVStream *st, AVPacket *pkt,
45	uint32_t *timestamp,
46	const uint8_t *buf, int len, uint16_t seq,
47	int flags)
48	{
49	int config_packet, start_packet, end_packet;
50
51	if (len < 2)
52	return AVERROR_INVALIDDATA;
53
54	config_packet = buf[0] & 0x40;
55	start_packet = buf[0] & 0x20;
56	end_packet = buf[0] & 0x10;
57	buf += 2; // ignore buf[1]
58	len -= 2;
59
60	if (config_packet) {
61
62	av_freep(&st->codecpar->extradata);
63	st->codecpar->extradata_size = 0;
64
65	if (len < 2 || ff_alloc_extradata(st->codecpar, len + 8))
66	return AVERROR_INVALIDDATA;
67
68	memcpy(st->codecpar->extradata, "SEQH", 4);
69	AV_WB32(st->codecpar->extradata + 4, len);
70	memcpy(st->codecpar->extradata + 8, buf, len);
71
72	/* We set codec_id to AV_CODEC_ID_NONE initially to
73	* delay decoder initialization since extradata is
74	* carried within the RTP stream, not SDP. Here,
75	* by setting codec_id to AV_CODEC_ID_SVQ3, we are signalling
76	* to the decoder that it is OK to initialize. */
77	st->codecpar->codec_id = AV_CODEC_ID_SVQ3;
78
79	return AVERROR(EAGAIN);
80	}
81
82	if (start_packet) {
83	int res;
84
85	ffio_free_dyn_buf(&sv->pktbuf);
86	if ((res = avio_open_dyn_buf(&sv->pktbuf)) < 0)
87	return res;
88	sv->timestamp = *timestamp;
89	}
90
91	if (!sv->pktbuf)
92	return AVERROR_INVALIDDATA;
93
94	avio_write(sv->pktbuf, buf, len);
95
96	if (end_packet) {
97	int ret = ff_rtp_finalize_packet(pkt, &sv->pktbuf, st->index);
98	if (ret < 0)
99	return ret;
100
101	*timestamp = sv->timestamp;
102	return 0;
103	}
104
105	return AVERROR(EAGAIN);
106	}
107
108	static void svq3_close_context(PayloadContext *sv)
109	{
110	ffio_free_dyn_buf(&sv->pktbuf);
111	}
112
113	RTPDynamicProtocolHandler ff_svq3_dynamic_handler = {
114	.enc_name = "X-SV3V-ES",
115	.codec_type = AVMEDIA_TYPE_VIDEO,
116	.codec_id = AV_CODEC_ID_NONE, // see if (config_packet) above
117	.priv_data_size = sizeof(PayloadContext),
118	.close = svq3_close_context,
119	.parse_packet = svq3_parse_packet,
120	};
121